Pulverizer



H2, 1930. w. A; WHITE 1,172,974

PULVERI ZER Filed July 11, 1929 2 Sheets-Sheet 1 Aug. 12, 1930?. w. A. WHHTE v1,722,974

PULVERI ZER 1 Filed July 11. 1929 2 Sheets-Sheet 2 Mme m6 Patented Aug. 12, 1930 UNITED STATES 'WILLIAIA LBEBT WHITE, 01' HEBBUBN-ON-I'YHE, ENGLAND rctvnarzm Application filed July 11, 1928, Serial No. 377,545, and in Great Britain August 21, 1823.

The invention relates to pulverizers and especially those for reducing coal to powder k for land or marine power plants.

Figure 1 shows an elevation for the most part in section of one form of the invention in which the two sets of blades are disposed at It the same distance from the axis of rotation. Figure 2 shows a side elevation of one of the blade-carrying elements and Figure 3 an end elevation artly in section of the two blade-carrying e ements in their relative working position;

Figure 4 shows a modified form of pulverizer in which one set of blades is disposed outside the other; while finally Figure 5 shows a section through the blades 2 taken on the line 55 of Figure 4.

Arrows in the diiierent figures show the direction of rotation of the parts to which they relate.

lin carrying the invention into efiect arc-- so cording to the illustrative form shown in Figures 1, 2 and 3, the pulverizer itself consists of two juxtaposed co-axial shrouds, A, B, rotatable in opposite directions, and carrying respectively beater blades, 2*, 2", disposed 3 at the same radial distance from the axis pi rotation.

The shrouds, A and B, are similar, corresponding parts in or associated with the two shrouds being denoted in the figures by the same numeral with the appropriate suflix a or b? The shroud, A, to be described by way of example, takes the form of a fiat centre plate, 3 or the like mounted on a shaft or spindle, 4 and provided with apertures, 5", for the incoming material, the peripheral portion, 6", of the shroud being dished towards the juxtaposed shroud in such a way that the cross section of the dished portion approximates to 5- a quarter ofa circle.

The heater blades, 2, themselves which take theform of flat plates or webs, project inwardly from their shrouds and are inclined away therefrom (see Figure 3) about a substantially radial axis in a direction opposite It to the direction of rotation so as to throw the material against the juxtaposed shroud.

Preferably, the beater blades are renewable andfor this purpose may be introduced radially through appropriately-angled slots, 6t 7*,i11 the peripheral part, 6' oi the shroud and secured to lugs, 8, thereon, radial grooves, 9, being provided in the fiat central part, 3, of the shroud to assist in positioning the blades.

In the case of the shroud, B, the apertures, 5, serve for the outgoing material.

Finally, the oppositely-running bladecarryin shrouds are enclosed in a suitable casing provided with the necessary ducts, 7 10, 10", respectively for the incoming and outgoing material.

The shafts or spindles, 4, r, on which the two juxtaposed and oppositely-running shrouds are mounted are disposed with their axes horizontal and are separately driven by the electric motors, 11, 11", or alternatively, they may be geared together and driven from a single motor.

The coal to be pulverized is fed to the pulverizer by any appropriate means such as the well-known rotating table, indicated at a, and driven by a chain drive,-b, and worm and wormwheel, c and d, from the pulverizer shaft, l

In association with the table, a, a sleeve, 8, with adjusting handle, e, and scoop, f, with adjusting handle, 7'', are also provided, while the hop er receiving coal from the bin or the like is s own at h, and the hot-air inlet at 2'.

The coal enters through 'the a ertures, 5, more or less towards the centre 0 the shroud,

A, is pulverized by attrition and drawn off through the apertures, 5", more or less towards the centre of the shroud, B, by a fan, 95 D, mounted as shown by way of example in Figure 1, on the shaft, 4", of the pulverizer, the general course of the coal through the apparatus being shown by arrows.

According to a modified form of the inventhe lane of which is disposed at rig tion, (see 4 and 5) the blades associated with e two shrouds, E and F, are at plates disposed in planes perpendicular to the shrou carrying them, the lanes of the blades bein non-radial (see igure 5) so that, if produced, they do not pass throu h the axis of rotation of the blade-carrying e ements.

The rings of beater blades on the two shrouds, E and F, are disposed one outside the other at difierent radial distances so that the material to be pulverized after passing through appropriate apertures, 5', near the centre of t e shrouds, E, is directed radially outwards "by a suitably shaped 12',

keyed to the shaft, 4', and is thrown y the inner set of inclined blades, 2', radiallyoutwards against the second set, 2', the inclination of the blades of the second set, 2', bein such as to tend to throw the material bac against those of the first set, 2.

To secure this action the inner edgesiof the beater blades of the inner set, 2', preclk-le @the outer ed es as the beater element rotates,

whereas in t e outer set, 2, the inner edges of the beater blades follow the outer edges. (See Figure 5.)

The material thus pulverized is drawn of! b a fan or otherwise as before through suitably shaped ducts including passages, 5', through the late shroud of the second element and a directing fitting, 12, keyed to its shaft, 4*.

As in the form of the invention above described, the two shafts, 4 and 4, may be supplied with separate motors driving them in opposite directions or they may be geared together and driven from a single motor.

As opposed to the usual pulverizers now in use having only one rota-ting set of blades, a pulverizer constructed in accordance with the present invention for the same speed of revolution has an increased output and efiiciency.

I wish it to be understood that variations may be made in the details of construction of the im roved pulverizer without departing from t e spirit of the invention, while it is applicable not only to the pulverizing of coal but of many other materials.

Having now described my invention what relatively=rotatable elements, each ccmprls=' ing a shroud with a rtures near the axis thereof and mounted t ereon a series of beater blades directed towards the other shroud, said series being so an led as to tend to throw the material to be u verized from one series to the other and t us maintain the material in the zone of pulverization; together with feeding and withdrawal ducts in operative relation to the apertures in said shrouds and disposed on opposite sides of said casing.

2. A pulverizer as claimed in claim 1, in which each of said shrouds is in ri 'd' association not only with said beater b ades but also with a centrally-disposed directin memher, said a rtures through said shrou being in opirative juxtaposition to said directing mem r and at a distance from said axis less than the distance of said beater blades.

3. A pulverizer as claimed in claim 1, in

which said shrouds are eripherall dished towards oneanother, said beater bla' es being included at least in part within said peripherally-dished rtions. 4. The combination of a "ulverizer shroud having slots and detacha le beater blades carried by said shrouds and ositioned in relation thereto by help of said slots.

5. The combination of a pulverizer shroud having slots and radially-disposed locatin means; and detachable beater blades carri by said shrouds and positioned in relation thereto by help of said slots and said locating means.

6. A pulverizer comprising in combination, co-axial relatively-rotatable elements, each comprising an a rtured shroud and carried thereby a series of beater blades, shafts on which said elements are respectivel mounted, a duct leading material who u verized to one of said shrouds, a duct lea pulverized material away from the other of said shrouds, said ducts registering with said apertures and shaped d1recting means in rigid association with said shrouds and disposed nearer the axis of rotation than said apertures, said directing means conforming with said leading ducts.

7. A pulverizer comprising in combination, co-axial rotatable elements, each comprising a shroud and mounted thereon a series of beater blades, juxtaposed shafts arranged end to end and .respectively carrying said shrouds together with oppositely-disposed shaped directing means mounted respectively onthe adjacent ends of said shafts.

In testimony whereof I have signed my name to this s cification.

WILI lAM ALBERT WHITE. 

